Submarine boat



FIG. 1 is a perspective view of the submarine boat;

FIG. 2 is a side elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a front end view thereof; and,

FIG. 6 is a rear end view thereof.

The ornamental design for a submarine boat, as shown.